JP2003214659A - Outdoor unit of air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an outdoor unit of an air conditioner which improves the degree of operation freedom of the air conditioner by efficiently and stably cooling an inverter device for driving a compressor with variable speed, and thereby improves the reliability of the inverter. <P>SOLUTION: This outdoor unit 30 of an air conditioner 10 is provided with an outdoor heat exchanger 17, a blower 18 for the heat exchanger 17, two compressors 11 and 12, and inverter devices 21 and 22 for driving the compressors 11 and 12 with variable speed, respectively. In addition, the outdoor unit 30 has an inverter output frequency control means 24 for controlling the output frequencies of both the inverter devices 21 and 22 so as to set the output frequency of one-side inverter device 21 (22) larger than that of the other-side inverter device 22 (21) in operation, a heat sink disposed at a position cooled by the air blasting from the blower 18, and heat generation components for the inverter devices mounted on the heat sink. The heat generation component for the inverter 21 is mounted on the windward side of that of the inverter device 22. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outdoor unit for a heat pump type air conditioner, and more particularly to an outdoor unit for an air conditioner in which a cooling structure of an inverter device which drives two compressors at variable speeds is improved.

[0002]

2. Description of the Related Art Conventionally, there is a split type air conditioner of this type in which an indoor unit and an outdoor unit are separated,
The outdoor unit used in this split type air conditioner is
There is one in which a machine room that houses a compressor and an accumulator and a heat exchange room that houses an outdoor heat exchanger, an outdoor fan, and the like are partitioned by a partition plate.

In addition, the split type air conditioner is provided with two compressors in the outdoor unit in order to improve the capacity, and each compressor is driven at a variable speed by an inverter device so that a large cooling and heating capacity is obtained. Things are being considered.

On the other hand, the inverter device for driving the compressor of the air conditioner at a variable speed requires cooling because the converter part and the inverter part are provided with respective heat-generating components.

The cooling of the conventional inverter device is disclosed in Japanese Patent Application Laid-Open No.
As disclosed in Japanese Patent Publication No. 01-201108, it is performed by attaching each heat-generating component of the inverter device to a heat-radiating plate made of aluminum, and the heat-radiating plate is designed to have a sufficient heat-radiating area for heat generated by each heat-generating component. Has been done.

[0006]

In order to secure a sufficient heat radiation area of the heat sink, it is necessary to enlarge the size of the heat sink, which may lead to an increase in the size of the inverter device.

On the other hand, the outdoor unit of the air conditioner is required to be compact and compact due to structural restrictions, waterproofing, etc., and requirements for installation space. Should be as small as possible.

Further, in the case where two compressors are provided for improving the capacity of the air conditioner and each compressor is driven at a variable speed by each inverter device, each compressor requires an inverter device. For this reason, the area occupied by the inverter device is doubled, and not only is the size of the heat sink reduced,
There is a problem of how to arrange the cooling arrangement structure of the heat dissipation plate in order to effectively exert the inverter function without impairing it.

The present invention has been made in consideration of the above-described circumstances, and efficiently and stably cools an inverter device that drives two compressors at variable speeds to improve the reliability of the inverter device, It is an object of the present invention to provide an outdoor unit for an air conditioner, which improves the degree of freedom in operating the air conditioner.

Another object of the present invention is to efficiently and effectively dispose a heat radiating plate in the passage of cooling air in consideration of the amount of heat generated from each inverter device, thereby reducing the size and size of the heat radiating plate. An object is to provide an outdoor unit of an air conditioner with improved reliability of heat generating components.

Another object of the present invention is to provide an outdoor unit of an air conditioner that effectively and beforehand prevents the occurrence of resonance phenomena of two compressors and reduces noise.

[0012]

An outdoor unit for an air conditioner according to the present invention is provided in order to solve the above-mentioned problems.
As described above, in an outdoor unit of an air conditioner including an outdoor heat exchanger, a blower for the outdoor heat exchanger, two compressors, and an inverter device that drives each of the compressors at a variable speed, Inverter output frequency control means for controlling the output frequency of the two inverter devices, and cooling by the blower of the blower so that the output frequency of one inverter device becomes higher than the output frequency of the other inverter device during operation. A heat radiating plate disposed at a position corresponding to the heat radiating plate and a heat generating component of the inverter device provided on the heat radiating plate, and the heat generating component of the one inverter device is mounted on the windward side of the heat generating component of the other inverter device. It has been done.

Further, in order to solve the above-mentioned problems, an outdoor unit of an air conditioner according to the present invention has an outdoor heat exchanger and a blower for the outdoor heat exchanger, as set forth in claim 2. In an outdoor unit of an air conditioner comprising two compressors, an inverter device that drives each of the compressors at a variable speed, and an inverter device that drives the blower at a variable speed, the inverter device for driving the compressor is a converter. And an inverter unit, one of the compressor drive inverter devices is connected so that the output of the converter unit is supplied to the inverter unit of the blower drive inverter device, and is cooled by the blower blows air. Is installed at a position where a heat sink including a converter section and an inverter section of the compressor driving inverter device is installed, Converter unit and the inverter unit,
It is mounted on the windward side of the converter section and the inverter section of the other compressor driving inverter device.

Further, in order to solve the above-mentioned problems,
In the outdoor unit of the air conditioner according to the present invention, as described in claim 3, the inverter unit of the blower drive inverter device is mounted on the heat dissipation plate on the leeward side of the compressor drive inverter device. It is a thing.

Furthermore, in order to solve the above-mentioned problems, an outdoor unit for an air conditioner according to the present invention has an outdoor heat exchanger and a blower for this outdoor heat exchanger as set forth in claim 4. In an outdoor unit of an air conditioner including two compressors, an inverter device that drives each of the compressors at a variable speed, and an inverter device that drives the blower at a variable speed, the compressor driving inverter device includes: For driving both of the compressors, the converter unit and the inverter unit are provided so that the output frequency of one of the compressor driving inverter devices becomes higher than the output frequency of the other compressor driving inverter device during operation. An inverter output frequency control means for controlling the output frequency of the inverter device is provided, and in the one compressor driving inverter device, the output of the converter unit is for driving the blower. It is those connected to be supplied to the inverter unit of the inverter device.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an outdoor unit for an air conditioner according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a first embodiment of an outdoor unit for an air conditioner according to the present invention, and is a refrigeration cycle diagram applied to a split type air conditioner.

This split type air conditioner 10 is provided with two compressors 11 and 12 arranged in parallel, and has a large cooling / heating capacity of several horsepower (HP) to ten and several horsepower, for example, about 10 horsepower.

The high temperature / high pressure discharge refrigerant compressed by the compressors 11 and 12 is sent to the indoor heat exchanger 14 via the four-way valve 13 as shown by the solid arrow A, and the indoor heat exchanger 14 uses the indoor fan to blow the indoor fan. Refrigerant that is heat-exchanged with indoor air by 15 and heats the inside of the room, while the refrigerant that is cooled by heating the inside of the room and condensed is expanded by a reversible expansion valve 16 as an expansion mechanism and is decompressed to the outdoor heat exchanger 17 The outdoor fan 18 removes ambient heat and evaporates. The heat pump type refrigeration cycle 20 is configured so that the evaporated refrigerant is returned from the four-way valve 13 to the compressors 11 and 12 via the accumulator 19 and is subjected to the compression action again.

The cooling operation is performed by switching the four-way valve 13, and during this cooling operation, the refrigerant flows in the broken line portion B.
As shown in FIG.

The inverter devices 21 and 22 are shown in FIG.
And a converter unit 26 configured to rectify the power supply frequency, and an inverter unit 28 configured to convert the current rectified by the converter unit 26 into a desired output frequency via a smoothing capacitor 27 as a smoothing circuit. . Depending on the output frequency from the inverter unit 28, the compressors 11, 1
The second compressor motor 29 is operated at the required operating frequency.

The converter unit 26 of the inverter devices 21 and 22 is configured as a rectifier circuit by combining a plurality of rectifying diodes, and the inverter unit 28 is configured as an inverse conversion circuit by combining a plurality of switching transistors. In any case, the inverter devices 21 and 22
Of at least the converter unit 26 and the inverter unit 28
The electric component of is composed of a large number of heat-generating components.

Incidentally, in FIG. 1, the outdoor fan 18 is
For example, the fan is driven by being connected to a three-phase AC power supply 23 and being energized by the power supply 23.

On the other hand, the two compressors 11 and 12 arranged side by side
Are driven at variable speeds by the inverter devices 21 and 22, respectively, and the operating frequencies of the compressor motors of the compressors 11 and 12 are controlled. Each inverter device 21, 22 has
While being connected to the three-phase AC power supply 23, it is electrically connected to an inverter control circuit 24 as an inverter output frequency control means, and an output signal from the inverter control circuit 24 causes the output frequency of each of the inverter devices 21 and 22 to change. Controlled.

As shown in FIG. 3, the inverter control circuit 24 preferably has a frequency difference Δf between the output frequency of one inverter device, for example 21, and the output frequency of the other inverter device, for example 22 ,. In order to have a size of about several Hz or less, for example, about 1 Hz to 2 Hz,
It controls the operation of both inverter devices 21 and 22. When the output frequency required capacity is F (Hz), the output frequency of both inverter devices 21 and 22 is (F / 2 + Δf / 2)
And (F / 2-Δf / 2), and both inverter devices 2
By slightly differentiating the output frequencies of 1 and 22 by the frequency difference Δf, the natural frequencies generated in both compressors 11 and 12 are made different, and resonance phenomena are prevented from occurring during operation, and operation noise is reduced. I am trying to

Further, the frequency difference Δf between the output frequencies from the inverter devices 21 and 22 is set to a small value of about 1 to 2 Hz so that the pressures in the compressors 11 and 12 are almost pressure balanced and the oil equalizing pipe 25 is used. This is to prevent the lubricating oil from being offset. If the pressures in both compressors 11 and 12 are different,
This is for preventing the lubricating oil of one compressor from being guided to the other compressor through the oil equalizing pipe 25 due to the pressure imbalance, and causing a shortage of the lubricating oil.

By the way, the air conditioner 10 comprises an outdoor unit 30 as shown in FIGS. 4, 5 and 6.

FIG. 4 is an external perspective view showing the outdoor unit 30 of the split type heat pump type air conditioner 10 according to the present invention,
5 is an exploded perspective view showing a part of the outdoor unit 30 in an exploded manner, and FIG. 6 is a plan view of FIG. As shown in these drawings, in the outdoor unit 30, a heat exchange chamber 31 having a rectangular cross section is formed in an upper portion thereof, and a machine chamber 32 is formed below the heat exchange chamber 31. It is separated from 32 by a partition plate 33. The heat exchanger 31 and the machine room 32 are surrounded by a plurality of side plate panels 34 to form an outer peripheral wall, and the upper surface of the heat exchange chamber 31 is covered with a flat plate 35 having a flat rectangular shape with a lid. The unit case is constructed by closing it.

The top plate 35 has, for example, a circular air outlet 36 at a substantially central portion of the lid portion 35a.
6, a cylindrical fan casing 37 is concentrically provided integrally or integrally with the fan casing 37, and the outdoor fan 18 is concentrically provided in the fan casing 37.

As shown in FIG. 5, in the machine room 32, a pair of left and right L-shaped installation legs 40a and 40b are integrally or integrally provided at both left and right ends of a bottom plate 39 made of a relatively thick rectangular flat steel plate or the like. On each of the even corners of the bottom plate 39, a plurality of columns 41 such as L-shaped steel are erected upright, and on these columns 41, 41,
A flat-bottomed rectangular drain tray 33 as a partition plate is placed and fixed, and the heat exchange chamber 3 above the drain tray 33 is fixed by the drain tray 33.
1 and the machine room 32 therebelow, respectively, while receiving the drain dropped from the pair of heat exchangers 17, collecting the water and discharging it from the rectangular cylindrical drain duct 44.

On the bottom plate 39 of the machine room 32, the compressors 11 and 12, the accumulator 19 and the like are arranged, while a pair of pipes 45 connecting them and a refrigerant pipe of an indoor unit (not shown) are connected. The pipe connection valve (packed valve) 46, the electrical component box 47, and the drain duct 44 are housed respectively.

As shown in FIG. 5, the electric parts box 47 is provided in a horizontally long rectangular box body, for example, inverter devices 21 and 22 (see FIG. 1) for controlling the rotational speeds of the compressors 11 and 12, an outdoor controller, and the like. The electrical components of the box are accommodated, and the upper end of the box body in the figure is fixed to, for example, the lower bottom surface of the drain tray 33.

On the inner bottom surface (upper surface in FIG. 5) of the rectangular drain tray 33, a pair of left and right heat exchangers 17 each formed in an almost obtuse angle L shape are erected so as to face each other. Each heat exchanger 17 is provided with a large number of heat exchange fins 17a made of vertically elongated rectangular thin plates arranged at a predetermined pitch, and arranged in parallel in the vertical direction from the upper end to the lower end of the fins 17a. A plurality of heat exchange tubes (not shown) penetrating the fins 17a in the plate thickness direction and ones vertically adjacent to each other at the outer ends of the heat exchange tubes are sequentially connected to each other.
A plurality of U bends 17b each forming a serpentine refrigerant passage. The refrigerant flow paths of these heat exchangers 17 are connected in series or in parallel.

Further, as shown in FIG. 6, the heat exchanger 17 has a horizontal side portion 17c extending horizontally in the upper and lower portions.
And an opposite side portion 17d which is bent from each one end of each of the horizontal side portions 17c at an obtuse angle into a substantially L shape and faces each other.

As shown in FIG. 6, the heat exchanger 17 is bent into a substantially obtuse L shape in plan view so that the side plate panels 34 are arranged so as to surround the outside of the L-shaped heat exchanger 17. ,
The heat exchanger 17 is inclined inward at a predetermined angle α with respect to each side plate panel 34, and each side plate panel 34 faces the heat exchange portion of each heat exchanger 17 as shown in FIG. The respective suction ports 34a are formed. The inside and outside of the heat exchange chamber 31 communicate with each other through these suction ports 34a.

Then, as shown in FIGS. 5 and 7, the drain duct 44 is arranged in the vicinity of the inner side surface of the electric component box 47 so as to vertically penetrate the machine chamber 32, and the upper surface opening 44a thereof is formed. The drain tray 33 penetrates in the plate thickness direction and opens as a drain drainage port, while the lower surface opening 44b penetrates the machine room bottom plate 39 in the plate thickness direction and slightly projects downward from the bottom plate 39 in the drawing to terminate. The opening is provided above the installation surface g of the outdoor unit 30.

Further, the drain duct 44 is divided into a drain drainage channel 51 and a cooling air duct 52 by dividing the inside by a partition wall 50 having a flat plate shape. The partition wall 50 extends below the electric component box 47 and extends to an axially intermediate portion in the drain duct 44 and terminates. Further, the heat sink cooling air passage 52 formed in the drain duct 44 penetrates the drain tray 33 and projects slightly upward to open.

As shown in FIGS. 7 and 8, the drain drainage port 44a is opened on the drain dish 33, and the drain collected on the drain dish 33 is drained from the drain drainage port 44a to the drain drainage channel 51. Is discharged through. Drain plate 33
The upper surface of the is inclined downward toward the drain drainage port 44a so as to collect drainage in the drain drainage port 44a and improve drainage efficiency. In addition, a ventilation port 44b that projects slightly upward from the drain drain port 44a of the drain tray 33 and opens.
The drain collected in the drain tray 33 is in the cooling air passage 5
I am prevented from being guided to 2.

As shown in FIGS. 7 and 9, a mounting hole 56 for mounting the heat sink 55 housed in the electric component box 47 is formed in the duct side wall 53 on the cooling air passage 52 side. A heat sink 55 is inserted into the hole 56 from the electric component box 47 side to the duct 44 side, and the heat sink 55 is exposed in the cooling air passage 52 in the duct 44 by the attachment of the heat sink 55.

When the heat pump type air conditioner 10 having the outdoor unit 30 constructed as described above is switched from the heating operation to the defrosting operation, the outdoor heat exchange is performed by the hot gaseous refrigerant passing through the outdoor heat exchanger 17. The frost on the outer surface of the container 17 is melted to generate drain water. This drain water is drain dish 3
The upper surface (inner bottom surface) 33a of the
Drain drain port 44 of drain duct 44 due to the inclination of 3a
a is collected, and as shown by the broken line arrow C in FIG.
The water is drained through the drain drainage channel 51e of the drain duct 44 from the lower surface opening 44b onto the installation surface g below the machine room bottom plate 39.

Moreover, since the drain duct 44 is housed in the machine room 32 and is not exposed to the outside of each side panel 34 at all, there is no discomfort, and the appearance of the outdoor unit 30 is not impaired, and the commercial property is improved. Can be made.

Further, since the lower end of the partition wall 50 of the drain duct 44 does not extend to the lower surface opening end 44b of the drain duct 44 and terminates at a position higher than the lower surface opening end 44b by a predetermined height, the height of the height is equal to that height. Only then, the drain water freezes and ice grows, and it is possible to secure a time until the lower surface opening end 44b of the drain duct 44 is closed by the ice.
Therefore, this drain duct 44 can be used for a long time as a drain drainage channel during the heating operation.

A partition wall 50 is formed inside the drain duct 44.
Since the drain drainage channel 51 and the cooling air passage 52 are partitioned by the axial direction, and the ventilation port 52a communicating with the cooling air passage 52 is made higher than the drain drainage port 44a by a predetermined height. The drain water above is the ventilation port 5
The heat sink 55 enters the cooling air passage 52 from 2a.
It is possible to prevent the deterioration of the electrical insulation due to the adhesion to the.

On the other hand, when the air conditioner is operated in the cooling mode, drainage does not occur in the outdoor heat exchanger 17, but the rotation of the outdoor fan 18 results in a lower temperature than the machine room bottom plate 39 as shown in FIG. The air in the space is sucked into the interior of the drain duct 44 through the lower surface opening 44b as indicated by the solid arrow D, passes through the cooling air passage 52 in the drain duct 44, cools the heat sink 55, and then enters the heat exchange chamber 31. It is sucked in and then exhausted to the outside from the air outlet 36 shown in FIG. Therefore, the heat sink 55 can be cooled sufficiently. Even during heating operation, the drain duct 44
The heat sink 55 is cooled by the cooling air passing through the internal cooling air passage 52.

By the way, the heat sinks 55 which are vertically spaced apart from each other in the cooling air passage 52 formed in the drain duct 44 have the heat radiating plates 58, respectively. The heat radiating plate 58 is inserted from the mounting hole 56 of the drain duct 44, and is fixed by a fastening means such as a bolt so as to project and be exposed in the cooling air passage 52. Then, the inverter devices 21 and 22 are attached to the respective heat dissipation plates 58 from the electric component box 47 side. Inverter devices 21 and 22 having a small heat generation amount are arranged in order from above.

Further, a metal material having a high thermal conductivity such as aluminum is used for each heat radiating plate 58 which radiates the heat generated from the inverter devices 21 and 22. A heat dissipation fin may be attached to increase the heat dissipation area of the heat dissipation plate 58. In this case, the radiation fins extend in the longitudinal direction of the cooling air passage 52.

Further, FIG. 7 shows an example in which a plurality of heat radiating plates 58 are provided in the cooling air passage 52 so as to be spaced apart from each other in the vertical direction. However, one heat radiating plate 58 is vertically formed and one heat radiating plate 58 is formed. Heat sink 5
In consideration of the amount of heat generation, each of the inverter devices 21 and 22 may be installed from the top to the bottom in the order of heat generation. In this case, the conductivity of the radiator plate 58 is combined with each other to positively cool with the cooling air passing through the cooling air passage 52.
The heat generation amount of each inverter device 21 and 22 can be suppressed and the heat generation temperature of each inverter device 21 and 22 can be made substantially equal.

By arranging the inverter device having a large heat generation amount on the windward side of the cooling air passage 52 and the inverter device having a small heat generation amount on the leeward side of the cooling air passage 52, the inverter device on the leeward side of the cooling air passage 52 is arranged more than that on the contrary. In the effect confirmation test of the heat generation temperature of the inverter device, the MAX temperature is about several degrees, for example, 6 degrees.
Could be reduced.

The heat generation temperature of this inverter device is set to MAX.
By reducing the temperature, it is possible to effectively prevent the quality deterioration of the heat generating parts of the inverter device and improve the reliability of the inverter device, and the inverter device can maintain the inverter function stably for a long period of time. In addition, it is possible to maintain the quality of the heat generating component and improve the reliability, and it is possible to improve the degree of freedom in the cooling and heating operation of the air conditioner.

FIG. 10 shows a refrigeration cycle to which the second embodiment of the outdoor unit for an air conditioner according to the present invention is applied.

In the air conditioner 10A shown in FIG. 10, the same components as those of the air conditioner 10 shown in FIG.

The air conditioner 10A shown in FIG. 10 is provided with an inverter device 60 that drives the outdoor fan 17 as a blower at a variable speed, and this inverter device 60 is linked to one side 22 of the compressor driving inverter device. As shown in FIG. 11, the output from the converter unit 26 of the compressor driving inverter device 22 is electrically connected so as to be supplied to the inverter unit 61 of the blower driving inter device 60. The operation of the fan motor 62 of the outdoor fan 17 is controlled by the output frequency from the inverter section 61.

In the air conditioner 10A shown in FIG. 10, the two compressors 11 and 12 provided in the outdoor unit 30 are driven at variable speeds by the two inverter devices 21 and 22, and the outdoor fan 18 is changed to another inverter device. It is driven by 60. The blower drive inverter device 60 is operation-controlled by one side 22 of the compressor drive inverter device.

In this case, the blower drive inverter device 6
0, the compressor driving inverter device 22 for controlling the operation of the inverter device 60, and the other compressor driving inverter devices 21 are generally large in the amount of heat generation: inverter device 22> inverter device 21> inverter device There are 60 relationships.

Therefore, as shown in FIGS. 12 (A) and 12 (B), the blower drive inverter device 60 having the smallest heat generation amount is arranged at the uppermost position, and then the compressor drive inverter device 21 is The inverter device 22 for driving the compressor, which generates the most heat, is arranged at the bottom.

For example, the compressor drive inverter device 2
Even if the Nos. 1 and 22 have the same specifications and are designed to have the same heat generation amount, the power source (for example, DC280V) for driving the outdoor fan 17 is supplied from the compressor driving inverter device 22 arranged below. As a result, the two compressor driving inverter devices 21 and 22 have different amounts of heat generation, and the inverter devices 60, 21, and 22 having the least amount of heat generation are arranged in this order from top to bottom.

Each inverter device 60, 21 and 22
Is the partition plate 6 that forms the cooling air passage 52A of the outdoor unit 30.
As shown in FIGS. 12 (A) and 12 (B), a plurality of mounting holes 66 are vertically spaced apart from each other in FIG.
6 A heat dissipation plate 67 made of aluminum or the like with excellent heat conduction characteristics
Are exposed so as to project into the cooling air passage 52A and are fixed by fastening means such as machine screws, and the inverter devices 60, 21 and 22 are sequentially attached to the radiator plates 67 from the upper side to the lower side and installed. It is a thing.

Each heat radiating plate 67 projects into the cooling air passage 52A and is exposed. On the other hand, each heat radiating plate 67 is integrally provided with a heat radiating cooling fin so as to increase the heat radiating area, and each of the inverter devices 60, 21. , 22 may be improved in cooling efficiency.

The cooling air passage 52A may be formed inside the drain duct 44 as shown in FIG. 7, or may be formed outside the drain duct 44. Even when it is formed outside the drain duct 44, the cooling air passage 52A is formed in the machine room 32 by the partition plate 65, and the cooling air flows along the cooling air passage 52A by the fan drive of the outdoor fan 18. It is designed to be sucked to the side.

The air conditioner 10A shown in FIG.
In the above, by electrically connecting one of the inverter devices 21 and 22 for driving the both compressors 11 and 12 to the blower drive inverter device 60, the inverter devices 21 and 22 are compressed with a frequency difference between the output frequencies. When the machines 11 and 12 are variably controlled, the inverter device 22 having a small output frequency is arranged on the windward side and the inverter device 21 having a large output frequency is arranged on the leeward side, and the inverter device 22 on the lower side is changed to the blower driving inverter device 60. When the output is supplied, each inverter device 21,
The heat radiation amount of 22 can be equalized. Further, by providing the inverter control circuit 24 and providing the frequency difference Δf between the output frequencies F output from the compressor driving inverter devices 21 and 22, the natural frequencies of the compressors 11 and 12 are made different to cause a resonance phenomenon. It is possible to reliably and reliably suppress the occurrence of noise and reduce operating noise.

Also, an example has been shown in which the respective inverter devices 60, 21 and 22 are independently attached to the respective heat sinks 67, 67, 67, but the heat sinks are made common to form one heat sink, Each inverter device 6 is attached to this one heat sink.
Considering the amount of heat generation, 0, 21 and 22 may be arranged so that the amount of heat generation becomes larger from the one having smaller heat generation to the lower one.

[0062]

In the outdoor unit for an air conditioner according to the present invention, each inverter device can efficiently and stably cool the inverter device that drives the two compressors at variable speeds. The heat generating parts are maintained below the required temperature, the quality deterioration of each heat generating part is effectively suppressed, the reliability of each inverter device is improved, and the inverter function can be stably maintained for a long time. The degree of freedom in driving can be improved.

Further, in the outdoor unit of the air conditioner according to the present invention, the heat radiation plate to which each inverter device is attached is considered in the cooling air passage from the windward side to the leeward side or the heat radiation amount is equalized. Since the air conditioners are arranged efficiently, the heatsink can be made smaller and more compact even if the cooling and heating capacity of the air conditioner is increased, and the heat-generating components can be efficiently and positively cooled to improve reliability. .

Further, in the outdoor unit of the air conditioner according to the present invention, the frequency difference is provided between the output frequencies from the respective inverter devices for driving the two compressors at variable speeds.
It is possible to suppress the occurrence of a resonance phenomenon during the operation of both compressors in advance and effectively, and it is possible to effectively and effectively reduce the operating noise.

[Brief description of drawings]

FIG. 1 is a refrigeration cycle diagram showing an embodiment of an outdoor unit of an air conditioner according to the present invention.

FIG. 2 is a schematic circuit diagram showing an inverter device that drives a compressor incorporated in the air conditioner shown in FIG. 1 at a variable speed.

FIG. 3 is a diagram showing the relationship between the output frequency and the required capacity of each inverter device that causes two compressors incorporated in the air conditioner shown in FIG. 1 to operate with a difference in operating frequency.

FIG. 4 is a perspective view showing an embodiment of an outdoor unit of an air conditioner according to the present invention.

FIG. 5 shows an embodiment of an outdoor unit for an air conditioner according to the present invention, and is a plan view of the outdoor unit with a side panel that is a main body casing removed.

6 is a plan view of the outdoor unit of the air conditioner shown in FIG.

7 is a cross-sectional view showing a cooling structure of an inverter device formed in a machine room of the outdoor unit of the air conditioner shown in FIG.

8 is a perspective view of the cooling structure of the inverter device in the machine room of the outdoor unit of the air conditioner shown in FIG. 5, as viewed from the heat exchange chamber side.

9 is a side view schematically showing an outdoor unit of the air conditioner shown in FIG.

FIG. 10 is a refrigeration cycle diagram showing another embodiment of the outdoor unit of the air-conditioning apparatus according to the present invention.

11 is a circuit diagram of an inverter device incorporated in the air conditioner shown in FIG. 10 to drive the compressor and the outdoor fan at a variable speed.

12A and 12B are a longitudinal sectional view and a side view showing a cooling structure of the inverter device installed in the machine room of the outdoor unit of the air conditioner shown in FIG.

[Explanation of Codes] 10,10A Air conditioner 11,12 Compressor 13 Four-way valve 14 Indoor heat exchanger 15 Indoor fan 16 Reversible expansion valve (expansion mechanism) 17 Outdoor heat exchanger 18 Outdoor fan (blower) 19 Accumulator 20 Refrigeration cycle 21, 22 Inverter device 23 Three-phase AC power supply 24 Inverter control circuit (inverter output frequency control means) 26 Converter unit 27 Smoothing capacitor 28 Inverter unit 30 Outdoor unit 31 Heat exchange chamber 32 Machine room 33 Partition plate (drain tray) 34 Side plate panel 35 Top plate 37 Fan casing 39 Bottom plate 41 Strut 44 Drain duct 44a Drain drainage port 45 Piping 46 Piping connection valve 47 Electrical component box 50 Partition wall 51 Drain drainage channel 52 Cooling air passage 52a Ventilation port 55 Heat sink 56 Mounting hole 60 Blower Drive inverter device 61 in Butter part 62 Fan motor 65 Partition plate 66 Mounting hole 67 Heat sink

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Sohiro Kobayashi             336 Tatehara, Fuji City, Shizuoka Prefecture Toshiba Carrier             Engineering Co., Ltd. F-term (reference) 5H007 AA06 BB06 CA01 CB02 CC01                       CC03 CC09 HA06

Claims (4)

[Claims] 1. An outdoor unit of an air conditioner comprising an outdoor heat exchanger, a blower for the outdoor heat exchanger, two compressors, and an inverter device that drives the compressors at variable speeds, respectively. Inverter output frequency control means for controlling the output frequency of the two inverter devices, and cooling by the blower of the blower so that the output frequency of the inverter device becomes higher than the output frequency of the other inverter device during operation. A heat radiating plate arranged at a position and a heat generating component of the inverter device provided on the heat radiating plate, and the heat generating component of the one inverter device is mounted on the windward side of the heat generating component of the other inverter device. The outdoor unit of the air conditioner, which is characterized by that. 2. An outdoor heat exchanger, a blower for the outdoor heat exchanger, two compressors, an inverter device that drives the compressors at variable speeds, and an inverter device that drives the blowers at variable speeds. In an outdoor unit of an air conditioner provided, the compressor driving inverter device has a converter part and an inverter part, and one of the compressor driving inverter devices has an output of the converter part is the blower driving inverter device. In addition to being connected so as to be supplied to the inverter section of the
A heat dissipation plate having a converter section and an inverter section of a compressor driving inverter device is installed, and the converter section and the inverter section of the one compressor driving inverter device and the converter section of the other compressor driving inverter device are installed. An outdoor unit for an air conditioner, which is installed on the windward side of the inverter section. 3. The outdoor unit for an air conditioner according to claim 2, wherein the inverter unit of the blower drive inverter device is mounted on the heat dissipation plate further downwind than the compressor drive inverter device. 4. An outdoor heat exchanger, a blower for this outdoor heat exchanger, two compressors, an inverter device that drives each of the compressors at a variable speed, and an inverter device that drives the blower at a variable speed. In an outdoor unit of an air conditioner provided, the compressor driving inverter device has a converter part and an inverter part, and the output frequency of one compressor driving inverter device is the other compressor driving inverter device. An inverter output frequency control means for controlling the output frequency of both the compressor driving inverter devices is provided so as to become higher than the output frequency during operation. An outdoor unit for an air conditioner, which is connected so that an output is supplied to an inverter unit of the blower driving inverter device.